As per new philisophy of Research Enginners , 2020 connect edition ., it is mentioned in the manual that STAAD files can be direcly imported to PLAXIS in IFC mode.

How to use connect editon in managing IFC biles in between Bentley Softwares.

I.E. STAAD to PLAXIS 3D, SOIL Vision to PLAXIS 3D., BIM Modeler to BRIDGE DESIGN (Leap Concrete + Leap Steel) and same again to PLAXIS 3D to check differantial setltement.